2008 Mazda RX-8 - ECU Tuning In The Internet Age - Project RX-8 - Modified Magazine

Hidden deep within the Tonto National Forest outside Phoenix is a cave with a triangle-shaped entrance. Within this cave lives a hermit with a high-speed Internet connection and an insatiable appetite for the unique power delivery of Mazda’s Renesis rotary engine. Some say he douses his morning bowl of cereal with Idemitsu premix rotary lubricant. Others claim to have seen him Wankeling his eccentric shaft in public. All we know is, he’s called MazdaManiac!

Communication with MazdaManiac is done in a very specific and high-tech way using his website and Google Talk. Should you deviate from the detailed instructions given to you, all hope of having your Mazda RX-8 (or Mazdaspeed3 or 6) Cobb AccessPort e-tuned via his remote calibration service may be lost (or at least delayed a bit). Like most solitary and highly intelligent creatures, an inability to follow simple instructions is particularly annoying to MazdaManiac, so don’t poke the bear by attempting to request his services in some other fashion (though one-on-one tuning sessions on a chassis dyno can also be arranged for bar mitzvahs and other special occasions).

Having followed MazdaManiac’s instructions on how to install his base calibration on our Cobb AccessPort and then flashing the RX-8’s factory ECU with it, we collected the required idle and cruising (at 4,200 rpm in Fourth gear) data logs. The log files and the answers to MazdaManiac’s “11 Deadly Questions” (including details about your car and any relevant modifications made to it) were then transferred to his secret location via Google Talk. Less than an hour later we received a new calibration, which we reflashed the factory ECU with using the AccessPort.

With this v1 e-tune now controlling our freshly built Renesis, we repeated the data-logging procedure with the added step of a Second gear wide-open-throttle pull from 3,000 rpm to redline and a Third gear wide-open-throttle pull from 3,500 to redline (fuel cut at 9,500 rpm). As per instructions, we watched the air/fuel ratio closely during the blast to redline, and although it was a touch leaner than we would have liked, there was no reason to back out of it. These new logs were transferred to MazdaManiac just like the first set was, and after a slice of pizza and an episode of Modern Family, there was a link to the v2 calibration waiting for us in Google Talk along with a message that read, “The tune is good. Beat on it.” You don’t have to tell us twice!

With a little extra Google Talk messaging, we learned that MazdaManiac focused the v1 calibration on customized adjustments to the MAF curve based on our first set of logs and the v2 calibration added custom-tailored fuel curves. MazdaManiac has tuned more than 1,000 Renesis engines in his day, so it’s unlikely there’s anyone else on the planet with as much Renesis-specific knowledge as this rotary mad scientist, and he’s understandably secretive about certain aspects of his tunes. This means any adjustments he’s made to the oil metering pump, ignition coil dwell time, or other areas where the Renesis needs special attention remain on lockdown, as do his Pro tuned calibration files (meaning they can’t be opened or modified in Cobb Tuning’s AccessTuner Race software designed for DIY or non-Pro service tuning).

Although MazdaManiac has yet to get aggressive with our ignition timing maps, the results of the v2 calibration have been extremely satisfying. We haven’t put the car on a chassis dyno yet since we’re going to wait until after v3 or v4 is completed during our next online encounter with MM (his online custom calibration service schedule is available at MazdaManiac.com), but both the butt dyno and the AccessPort’s performance testing functions suggest we have a very healthy Renesis on our hands.

In fact, the AccessPort’s dyno simulator returned rather optimistic numbers (perhaps because our curb weight estimate was too high and rear wheel height is a bit shorter than stock), showing a peak of just under 280 hp at 8,600 rpm and 202 lb-ft at 6,800 rpm. In reality that’s probably somewhere between crank horsepower and wheel horsepower, but it’s still a promising start. The 0-60-mph and quarter-mile tests we did with the Cobb AccessPort and Driftbox (to verify the Cobb numbers) also left us feeling optimistic about our new Renesis’ output, with a best 0-60 time of 5.2 seconds and a quarter-mile of 13.6 seconds. That’s a pretty solid improvement over the RX-8’s stock figures of 0-60 in 6.5 seconds and 15 seconds to cover the quarter-mile.

We’re looking forward to our next online exchange of data logs and calibrations with the enigmatic Mazda Maniac and providing chassis dyno charts documenting each stage in the process in an upcoming issue.

Cobb AccessPort
For those of you who aren’t familiar with Cobb Tuning’s AccessPort, this cellphone-sized device is an incredibly versatile and powerful tool. Not only does it allow you to reflash the factory ECU via the OBD-2 port, permitting custom tuning of fuel and ignition maps and many other parameters that enhance engine performance, it also allows you to watch engine data live or log it for later review. It’s also a scan tool for reading and diagnosing engine codes, and it has performance-measuring capabilities like estimating horsepower, 0-60 times, quarter-mile times, and more.

The AccessPort is widely used in the Subaru, Mitsubishi, Mazda, BMW, and R35 GT-R communities, while the RX-8–specific AccessPort can only be purchased from MazdaManiac.com. Not that that’s a bad thing, since for just $594 you get the power off the AccessPort and MM’s custom calibration services (or just the AP for $495). When you consider how much performance the AccessPort and MM’s calibrations can unlock, you’d be hard-pressed to find another mod that comes even close in the bang-for-your-buck or enjoyment-enhancing departments.